Sound

This computer is using the CA0132 chipset.
Alsa should work out of the box except for some bugs.

For those using 3.8 kernel note that card sometimes will do random noise that can be fixed by reloading the corresponding module saying that buffer position should be fixed:

rmmod snd_hda_intel
modprobe snd_hda_intel position_fix=1

If you loose sound after system wake you can recover it by rebooting into Windows and booting Linux again. I believe this has to do with a firmware problem.
There's also no headphone detection.

In kernel 3.9 firmware problem seems to be fixed and headphone detection is working (If speakers don't automute go to alsamixer and unmute HP/Speaker Auto Detect). A lot of channels and fx were added to alsa.

Touchpad

TODO

Video

Since kernel 3.5 PRIME technology is officially supported by the nouveau graphic drivers. This means that Nvidia Optimus used in this computer is supported. Anyway you need to install bumblebee for letting vgaswitcheroo disable your graphics card.

In kernel 3.7 power managing methods were add so that battery life increased a lot.

AlienFX

AlienFX on Alienware M14xR2 is only supported by pyalienfx that can be installed from AUR.